American Thoracic Society International Conference
American Thoracic Society International Conference
May 18, 2015
2 min read

E-cigarette use may not result in long-term smoking cessation

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DENVER — The use of electronic-cigarettes greatly improved the likelihood of smoking abstinence in study participants after 1 month, but the effect diminished at later follow-ups, according to data presented at the American Thoracic Society International Conference.

“From our meta-analysis, looking at smoking abstinence, we found out that at 1 month there was a statistically significant effect in achieving smoking abstinence comparing e-cigarette to placebo e-cigarette,” Riyad Al-Lehebi, MD, respirology fellow at the University of Toronto, told “But when we looked into the long-term effect at 3 and 6 months, we no longer found significant effects on quitting.”

Al-Lehebi and colleagues searched Medline and Embase from 1946 to May 2014 and conducted a meta-analysis on the efficacy and safety of e-cigarettes for promoting smoking cessation in 1,011 participants. The investigators also examined additional studies that reported adverse events of e-cigarettes among 1,212 participants.

The results indicated abstinence was significantly better after 1 month for those who used e-cigarettes when compared with placebo (RR = 1.71; 95% CI, 1.08-2.72). Minimal differences in abstinence, however, were observed at 3 months (RR = 1.95; 95% CI, 0.74-5.13) and 6 months (RR = 1.32; 95% CI, 0.59-2.93).

In an included study that evaluated continued abstinence at 6 months, results were comparable between e-cigarettes and placebo (7.3% vs. 4.1%; RR = 1.77; 95% CI, 0.54-5.77) or open-label nicotine patch (7.3% vs. 5.8%; RR = 1.26; 95% CI, 0.68-2.34).

Adverse events associated with e-cigarette use included shortness of breath, throat irritation and dry cough.

Al-Lehebi told that comparative studies reported more frequent serious adverse events among participants who used e-cigarettes than users of open-label nicotine patch (19.7% vs. 11.8%; RR = 1.97; 95% CI, 1.05-3.68). Serious adverse events, however, were comparable between users of e-cigarettes and placebo e-cigarettes (RR = 1.36; 95% CI, 0.54-3.42).

“There is a paucity of data, and more long-term studies are needed to determine the efficacy and safety of e-cigarettes,” Al-Lehebi said. “To label e-cigarettes as a safer alternative is questionable.” – by Ryan McDonald


Al-Lehebi RO, et al. Abstract 65842. Presented at: American Thoracic Society International Conference; May 15-20, 2015; Denver.

Disclosure: Al-Lehebi reports no relevant financial disclosures.